Who is included: employers with more than 1,000 worldwide employees in at least one sourced year and a documented Bay Area workplace. All records includes unresolved and outside-tech cases; use the scope and industry filters to narrow the sample.
Reading the map: bubbles show workplaces or approximate city presence, not employee totals. Hollow bubbles are city-level records; cluster numbers count distinct employers. Click a bubble for dated evidence and sources. The dashed rectangle marks the study extent, not complete coverage.
Gaps are not closures: supported presence intervals remain visible; short carry-forwards are labeled estimated. Older observations appear only with “Show last-known locations,” and remain unverified. Confirmed closures or departures suppress the affected locations. All recorded years combines observations from different dates.
